Pub Date : 2015-06-29DOI: 10.1109/EVER.2015.7138047
Andrii Stefanskyi, L. Starzak, A. Napieralski
The success of electric vehicle drives heavily depends on the maximization of energy conversion efficiency. Losses in power electronic converters increase system size, weight and cost, raise energy demand and limit the operating distance range. Advances in semiconductor technology can remedy these problems and silicon carbide devices are of special interest in this context. This material enables manufacturing high-voltage devices with lower on-state voltage drop and shorter switching times, thus reducing both static and dynamic power loss. In this paper, recent achievements in silicon carbide technology as well as their applications in electrical vehicles have been reviewed.
{"title":"Silicon carbide power electronics for electric vehicles","authors":"Andrii Stefanskyi, L. Starzak, A. Napieralski","doi":"10.1109/EVER.2015.7138047","DOIUrl":"https://doi.org/10.1109/EVER.2015.7138047","url":null,"abstract":"The success of electric vehicle drives heavily depends on the maximization of energy conversion efficiency. Losses in power electronic converters increase system size, weight and cost, raise energy demand and limit the operating distance range. Advances in semiconductor technology can remedy these problems and silicon carbide devices are of special interest in this context. This material enables manufacturing high-voltage devices with lower on-state voltage drop and shorter switching times, thus reducing both static and dynamic power loss. In this paper, recent achievements in silicon carbide technology as well as their applications in electrical vehicles have been reviewed.","PeriodicalId":169529,"journal":{"name":"2015 Tenth International Conference on Ecological Vehicles and Renewable Energies (EVER)","volume":"2022 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132846823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-01DOI: 10.1109/EVER.2015.7112950
Z. Zhu, H. Hua, D. Wu, J. T. Shi, Z. Wu
The partitioned stator (PS) machine adopts two stators to allocate coils and permanent magnets (PMs) separately, which can increase the space for PMs and coils to boost the electromagnetic torque and to improve the thermal condition of PMs which are on the stator. In this paper, the PS switched flux PM machine and PS flux reversal PM machine are proved to inherently share the same operating principle and the same machine topology but with interior PM (IPM) and surface-mounted PM (SPM) stators, respectively. Based on this concept, four PS machines with different PM excitation stator topologies are introduced and compared in terms of back-EMF, cogging torque, electromagnetic torque, torque per PM volume and flux-weakening capability. The results show that the spoke-IPM inner stator exhibits the maximum back-EMF and hence the largest average torque, while the IPM inner stator has the best flux-weakening capability and the V-shaped IPM (VIPM) produces the highest torque per PM volume.
{"title":"Comparison of partitioned stator machines with different PM excitation stator topologies","authors":"Z. Zhu, H. Hua, D. Wu, J. T. Shi, Z. Wu","doi":"10.1109/EVER.2015.7112950","DOIUrl":"https://doi.org/10.1109/EVER.2015.7112950","url":null,"abstract":"The partitioned stator (PS) machine adopts two stators to allocate coils and permanent magnets (PMs) separately, which can increase the space for PMs and coils to boost the electromagnetic torque and to improve the thermal condition of PMs which are on the stator. In this paper, the PS switched flux PM machine and PS flux reversal PM machine are proved to inherently share the same operating principle and the same machine topology but with interior PM (IPM) and surface-mounted PM (SPM) stators, respectively. Based on this concept, four PS machines with different PM excitation stator topologies are introduced and compared in terms of back-EMF, cogging torque, electromagnetic torque, torque per PM volume and flux-weakening capability. The results show that the spoke-IPM inner stator exhibits the maximum back-EMF and hence the largest average torque, while the IPM inner stator has the best flux-weakening capability and the V-shaped IPM (VIPM) produces the highest torque per PM volume.","PeriodicalId":169529,"journal":{"name":"2015 Tenth International Conference on Ecological Vehicles and Renewable Energies (EVER)","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122741708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-01DOI: 10.1109/EVER.2015.7112964
M. Tsai, Shaokai Lin, Sheng-He Wang
This paper presents a novel on-line condition monitoring method that is based on the input voltage and measured line current of a Brushless DC motor drive system. The time-frequency signal processing method of Hilbert Huang Transform is applied to extract the characteristic component of line current and then obtain the required equivalent electrical impedance, which is utilized for health monitoring. Gauge Repeatability & Reproducibility is employed to evaluate the reliability of the computed impedance during the training strategy. A health reference index defined from the characteristic intrinsic mode function is proposed for decision making during on-line monitoring. Theoretical analysis and experiments are conducted to evaluate the effectiveness of the proposed health monitoring approach.
{"title":"Condition monitoring of BLDC motor drive systems by Hilbert Huang Transform","authors":"M. Tsai, Shaokai Lin, Sheng-He Wang","doi":"10.1109/EVER.2015.7112964","DOIUrl":"https://doi.org/10.1109/EVER.2015.7112964","url":null,"abstract":"This paper presents a novel on-line condition monitoring method that is based on the input voltage and measured line current of a Brushless DC motor drive system. The time-frequency signal processing method of Hilbert Huang Transform is applied to extract the characteristic component of line current and then obtain the required equivalent electrical impedance, which is utilized for health monitoring. Gauge Repeatability & Reproducibility is employed to evaluate the reliability of the computed impedance during the training strategy. A health reference index defined from the characteristic intrinsic mode function is proposed for decision making during on-line monitoring. Theoretical analysis and experiments are conducted to evaluate the effectiveness of the proposed health monitoring approach.","PeriodicalId":169529,"journal":{"name":"2015 Tenth International Conference on Ecological Vehicles and Renewable Energies (EVER)","volume":"20 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114032945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-01DOI: 10.1109/EVER.2015.7112993
Matteo Giacomo Prina, G. Garegnani, D. Moser, U. F. Oberegger, Roberto Vaccaro, W. Sparber, M. Gazzani, G. Manzolini
The paper presents an analysis of the operating parameters of the Combined Cycle Gas Turbine (CCGT) systems in Italy in the years from 2006 to 2013, studying the environmental and economic impact of renewable energy sources spread on CCGT. Variable Renewable Energy (VRE) sources development, electricity demand reduction and CCGT overcapacity have affected the CCGT systems that have had to operate at partial load, experiencing several rump-up/down cycles in a day. The consequent increase of CO2 emission and costs have to be considered in a RES high penetration future scenario. The paper aims to evaluate the net avoided emissions by RES and the cost that Italy have incurred to avoid to emit a tonne of CO2. To reach the high penetration of RES targets the attention is switching from the problem of adding more renewable energy installations to the problem of managing the whole “green” electricity production in a smarter way. Considering all the indirect effects caused by RES on the electricity system is essential for everyone who wants to analyse future scenarios.
{"title":"Economic and environmental impact of photovoltaic and wind energy high penetration towards the achievement of the Italian 20-20-20 targets","authors":"Matteo Giacomo Prina, G. Garegnani, D. Moser, U. F. Oberegger, Roberto Vaccaro, W. Sparber, M. Gazzani, G. Manzolini","doi":"10.1109/EVER.2015.7112993","DOIUrl":"https://doi.org/10.1109/EVER.2015.7112993","url":null,"abstract":"The paper presents an analysis of the operating parameters of the Combined Cycle Gas Turbine (CCGT) systems in Italy in the years from 2006 to 2013, studying the environmental and economic impact of renewable energy sources spread on CCGT. Variable Renewable Energy (VRE) sources development, electricity demand reduction and CCGT overcapacity have affected the CCGT systems that have had to operate at partial load, experiencing several rump-up/down cycles in a day. The consequent increase of CO2 emission and costs have to be considered in a RES high penetration future scenario. The paper aims to evaluate the net avoided emissions by RES and the cost that Italy have incurred to avoid to emit a tonne of CO2. To reach the high penetration of RES targets the attention is switching from the problem of adding more renewable energy installations to the problem of managing the whole “green” electricity production in a smarter way. Considering all the indirect effects caused by RES on the electricity system is essential for everyone who wants to analyse future scenarios.","PeriodicalId":169529,"journal":{"name":"2015 Tenth International Conference on Ecological Vehicles and Renewable Energies (EVER)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129715140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-01DOI: 10.1109/EVER.2015.7112924
M. S. Camara, M. Camara, B. Dakyo, H. Gualous
This paper presents modeling and control strategies of 5MW Permanent Magnet Synchronous Generator (PMSG) for offshore wind energy conversion application. The PMSG is connected to electrical grid of 20kV phase to phase RMS voltage using a back-to-back converter. The contribution of this paper is focused on energy management strategies using “grid code”, where the required power profile is fixed by electrical grid manager without any consideration for wind speed variations. For this study, it is assumed that the available power is higher than required power for electrical grid. The proposed control strategies include a Maximum Power Tracking (MPPT) for PMSG speed control, active/reactive power control, and DC-bus voltage management. To show the performances of the control, some simulation results are presented and analyzed using Matlab/Simulink software.
{"title":"An offshore wind energy conversion system based on a Permanent Magnet Synchronous Generator connected to grid -modeling and control strategies","authors":"M. S. Camara, M. Camara, B. Dakyo, H. Gualous","doi":"10.1109/EVER.2015.7112924","DOIUrl":"https://doi.org/10.1109/EVER.2015.7112924","url":null,"abstract":"This paper presents modeling and control strategies of 5MW Permanent Magnet Synchronous Generator (PMSG) for offshore wind energy conversion application. The PMSG is connected to electrical grid of 20kV phase to phase RMS voltage using a back-to-back converter. The contribution of this paper is focused on energy management strategies using “grid code”, where the required power profile is fixed by electrical grid manager without any consideration for wind speed variations. For this study, it is assumed that the available power is higher than required power for electrical grid. The proposed control strategies include a Maximum Power Tracking (MPPT) for PMSG speed control, active/reactive power control, and DC-bus voltage management. To show the performances of the control, some simulation results are presented and analyzed using Matlab/Simulink software.","PeriodicalId":169529,"journal":{"name":"2015 Tenth International Conference on Ecological Vehicles and Renewable Energies (EVER)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126843747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-01DOI: 10.1109/EVER.2015.7112995
Yang Tang, Johannes J. H. Paulides, E. Lomonova
Flux-switching machines (FSMs) are a viable candidate for electric propulsion of hybrid/electric vehicles. This paper investigates the field weakening performance of FSMs. The investigation starts with general torque and voltage expressions, which reveal the relationships between certain parameters and the produced torque and induced voltage of this machine. Based on the understanding of these relationships, a number of methods for reshaping the torque-speed characteristic of an FSM design are proposed and validated using finite element analysis (FEA).
{"title":"Field weakening performance of flux-switching machines for hybrid/electric vehicles","authors":"Yang Tang, Johannes J. H. Paulides, E. Lomonova","doi":"10.1109/EVER.2015.7112995","DOIUrl":"https://doi.org/10.1109/EVER.2015.7112995","url":null,"abstract":"Flux-switching machines (FSMs) are a viable candidate for electric propulsion of hybrid/electric vehicles. This paper investigates the field weakening performance of FSMs. The investigation starts with general torque and voltage expressions, which reveal the relationships between certain parameters and the produced torque and induced voltage of this machine. Based on the understanding of these relationships, a number of methods for reshaping the torque-speed characteristic of an FSM design are proposed and validated using finite element analysis (FEA).","PeriodicalId":169529,"journal":{"name":"2015 Tenth International Conference on Ecological Vehicles and Renewable Energies (EVER)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126981312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-01DOI: 10.1109/EVER.2015.7112965
F. Marignetti, D. D'Aguanno, R. D. Di Stefano
This paper deals with the design of a synchronous machine using no brushes and no permanent magnets, in an efficient and economic layout. A self-excited machine is proposed. The space harmonics of the magneto-motive force are used to produce the excitation. The mathematical model is derived. The design optimization is aimed at maximizing the torque and reducing the mutual inductions between rotor windings.
{"title":"Design and optimization of self-excited synchronous machines with fractional slots","authors":"F. Marignetti, D. D'Aguanno, R. D. Di Stefano","doi":"10.1109/EVER.2015.7112965","DOIUrl":"https://doi.org/10.1109/EVER.2015.7112965","url":null,"abstract":"This paper deals with the design of a synchronous machine using no brushes and no permanent magnets, in an efficient and economic layout. A self-excited machine is proposed. The space harmonics of the magneto-motive force are used to produce the excitation. The mathematical model is derived. The design optimization is aimed at maximizing the torque and reducing the mutual inductions between rotor windings.","PeriodicalId":169529,"journal":{"name":"2015 Tenth International Conference on Ecological Vehicles and Renewable Energies (EVER)","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130578308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-01DOI: 10.1109/EVER.2015.7112920
M. Schier, N. S. Kumar
The requirements for the climatisation of electric vehicles largely depend on the vehicles usage location. For example, electric vehicles operated in European countries require heating during the winter season, while those operated in equatorial regions face cooling load throughout the year. To date, the low range for a given battery charge remains the single-most important factor hindering the widespread acceptance of electric vehicles. The principal electrical load of an electric vehicle used in equatorial regions comprises of the traction motor and the air-conditioning compressor motor. These high power loads expedites the battery drain, leading to poor cruise range. The paper proposes a novel design solution geared towards improving the overall operating efficiency of these motors by integrating them into a single housing.
{"title":"Design of a 2 in 1 motor to increase the efficiency of electric vehicles","authors":"M. Schier, N. S. Kumar","doi":"10.1109/EVER.2015.7112920","DOIUrl":"https://doi.org/10.1109/EVER.2015.7112920","url":null,"abstract":"The requirements for the climatisation of electric vehicles largely depend on the vehicles usage location. For example, electric vehicles operated in European countries require heating during the winter season, while those operated in equatorial regions face cooling load throughout the year. To date, the low range for a given battery charge remains the single-most important factor hindering the widespread acceptance of electric vehicles. The principal electrical load of an electric vehicle used in equatorial regions comprises of the traction motor and the air-conditioning compressor motor. These high power loads expedites the battery drain, leading to poor cruise range. The paper proposes a novel design solution geared towards improving the overall operating efficiency of these motors by integrating them into a single housing.","PeriodicalId":169529,"journal":{"name":"2015 Tenth International Conference on Ecological Vehicles and Renewable Energies (EVER)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126316738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-01DOI: 10.1109/EVER.2015.7112930
Fatma Ezzahra Lahouar, M. Hamouda, J. Ben Hadj Slama
This paper introduces a single-stage grid-connected photovoltaic power conversion system based on a three-phase three-level Neutral Point Clamped (NPC) converter. The main benefits of the proposed structure are the elimination of the intermediate DC/DC power conversion stage that is usually used to boost the dc-voltage and ensure MPPT operation. Therefore, two control schemes based on a current controller and an MPPT algorithm are handled in only one processing stage. The MPPT algorithm computes in real-time the dc voltage that should be applied across the PV generator so as to extract the maximum power. The output of the MPPT algorithm is thereafter considered as a reference of a current controller that should perform a perfect tracking of the dc-voltage reference and also near unity input power factor operation. The proposed photovoltaic power conversion topology and control method are tested by numerical simulations. The obtained results demonstrate that the designed PV conversion system provides effective response in steady state, fast and perfect tracking of the maximum power point, and robust in case of a partial shading.
{"title":"Design and control of a grid-tied three-phase three-level diode clamped single-stage photovoltaic converter","authors":"Fatma Ezzahra Lahouar, M. Hamouda, J. Ben Hadj Slama","doi":"10.1109/EVER.2015.7112930","DOIUrl":"https://doi.org/10.1109/EVER.2015.7112930","url":null,"abstract":"This paper introduces a single-stage grid-connected photovoltaic power conversion system based on a three-phase three-level Neutral Point Clamped (NPC) converter. The main benefits of the proposed structure are the elimination of the intermediate DC/DC power conversion stage that is usually used to boost the dc-voltage and ensure MPPT operation. Therefore, two control schemes based on a current controller and an MPPT algorithm are handled in only one processing stage. The MPPT algorithm computes in real-time the dc voltage that should be applied across the PV generator so as to extract the maximum power. The output of the MPPT algorithm is thereafter considered as a reference of a current controller that should perform a perfect tracking of the dc-voltage reference and also near unity input power factor operation. The proposed photovoltaic power conversion topology and control method are tested by numerical simulations. The obtained results demonstrate that the designed PV conversion system provides effective response in steady state, fast and perfect tracking of the maximum power point, and robust in case of a partial shading.","PeriodicalId":169529,"journal":{"name":"2015 Tenth International Conference on Ecological Vehicles and Renewable Energies (EVER)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123893660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-01DOI: 10.1109/EVER.2015.7112922
M. Balato, L. Costanzo, M. Vitelli
In mismatching operating conditions (due to clouds, shadows, soiling from dust, debris, manufacturing tolerances, non-uniform aging, different orientation of parts of the PV field, etc.) the energetic efficiency and the reliability of the Photovoltaic (PV) systems are strongly compromised. A possible solution adopt to mitigate the negative effects of the occurrence of mismatching conditions is represented by the dynamical reconfiguration of PV modules in the PV field. The goal of this paper is to demonstrate that, by using the dynamical reconfiguration of PV modules, it is possible to find a configuration which represent a suitable compromise between efficiency and reliability. Further work is needed and is in progress in order to design suitable re-configuration algorithms able to identify such compromise configurations.
{"title":"Optimization of both the energetic efficiency and the duration of life of PV arrays by means of the dynamical reconfiguration of PV modules connections","authors":"M. Balato, L. Costanzo, M. Vitelli","doi":"10.1109/EVER.2015.7112922","DOIUrl":"https://doi.org/10.1109/EVER.2015.7112922","url":null,"abstract":"In mismatching operating conditions (due to clouds, shadows, soiling from dust, debris, manufacturing tolerances, non-uniform aging, different orientation of parts of the PV field, etc.) the energetic efficiency and the reliability of the Photovoltaic (PV) systems are strongly compromised. A possible solution adopt to mitigate the negative effects of the occurrence of mismatching conditions is represented by the dynamical reconfiguration of PV modules in the PV field. The goal of this paper is to demonstrate that, by using the dynamical reconfiguration of PV modules, it is possible to find a configuration which represent a suitable compromise between efficiency and reliability. Further work is needed and is in progress in order to design suitable re-configuration algorithms able to identify such compromise configurations.","PeriodicalId":169529,"journal":{"name":"2015 Tenth International Conference on Ecological Vehicles and Renewable Energies (EVER)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130212699","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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